AB0415 CAN WE PREDICT THE RISK FACTORS FOR SWITCHING IN THE FIRST YEAR OF THERAPY WITH BDMARD IN PATIENTS WITH RHEUMATOID ARTHRITIS?
Authors: A. Martins, D. Santos Oliveira, R. Nicolau, T. Martins-Rocha, A. Bernardo, S. Pimenta, M. Bernardes, L. Costa
Journal: Annals of the Rheumatic Diseases (2023)

<h3>Background</h3> Biological Disease-modifying Antirheumatic Drugs (bDMARD) have improved the clinical course and quality of life of patients with rheumatoid arthritis (RA). However, some patients failed to respond or have an insufficient response to bDMARD, early in the course of the treatment, and the reasons why this happens aren't fully understood. <h3>Objectives</h3> To determine the percentage of RA patients who failed to respond to bDMARD and need to switch in the first year of treatment, describe their characteristics, and identify specific baseline features as possible predictors of bDMARD early failure. <h3>Methods</h3> An observational monocentric retrospective cohort study was conducted with RA patients (according to 2010 ACR/EULAR criteria), registered in the national database (Reuma.pt) that started their first bDMARD between June 2000 and December 2021 and had a minimum follow-up of 12 months. Demographic data, disease characteristics, laboratory parameters and treatment at baseline were collected. Disease activity scores (CDAI, SDAI and DAS-28-CRP), functional scores (HAQ) and clinical response to treatment (according to EULAR and ACR response criteria) were collected at 3, 6 and 12 months after the start of bDMARD. The proportion of patients who failed to respond (according to treat-to-target strategies) and who switched to another bDMARD was calculated. Patients who discontinued treatment in the first year due to adverse events were excluded. Chi-square test, t-test and Mann-Whitney U test were conducted (categorical, normally and not normally distributed continuous variables, respectively). Also, a multivariate logistic regression analysis was performed. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. A p-value &lt;0.05 was considered statistically significant. <h3>Results</h3> 437 (364 females, 83.3%) patients with RA were included. The mean age was 52.4 ± 11.4 years and the disease duration was 11.8 ± 8.8 years. The majority of these patients started an anti-TNF-α agent as their first bDMARD (n=315, 72.1%). The remaining patients started rituximab (n=66, 15.1%), tocilizumab (n=51, 11.7%) and abatacept (n=5, 1.1%). Forty-eight (11.0%) patients failed to respond to the bDMARD in the first year of treatment (mean duration of bDMARD treatment was 0.75 ± 0.3 years) and needed to switch to another bDMARD. Demographic characteristics were similar in the group of patients that switch due to ineffectiveness and patients that didn't switch in the first year. Disease activity scores (DAS-28-CPR, CDAI, SDAI) and HAQ at baseline were also similar in the two groups. There were significantly more current or former smokers in the group of patients that needed to switch in the first year of therapy (p=0.030). Moreover, depression was significantly more frequent in the switch group (p=0.003). Positivity for rheumatoid factor at baseline was also significantly more frequent in the switch group (p=0.014). Regarding the type of bDMARD, patients in the switch group were more frequently treated with anti-TNF-α agents than patients that didn't switch (p&lt;0.001). In the multivariate analysis, anti-TNF-α agents use (versus non-anti-TNF-α agents) (OR 8.3, 95% CI 2.4-28.8, p=0.001), tobacco exposure (OR 2.3, 95% CI 1.1-4.8, p=0.02) and history of depression (OR 3.1, 95% CI 1.3-7.7) seem to predict the bDMARD early failure and the need to switch in the first year of treatment. <h3>Conclusion</h3> In our study, anti-TNF-α agents were associated with a higher switch rate due to ineffectiveness in the first year of treatment in RA patients, when comparing to non-anti-TNF-α agents. Moreover, current and former smokers, patients with depression and with positive rheumatoid factor had a higher switch rate due to ineffectiveness. This study reinforces the importance of RA patients quit smoking, as tobacco may interfere with clinical response to bDMARD. Furthermore, routine screening for depression should be included in daily clinical practice and a multidisciplinary treatment approach should be offered to these patients. <h3>REFERENCES:</h3> NIL. <h3>Acknowledgements:</h3> NIL. <h3>Disclosure of Interests</h3> None Declared.